Author Archives: Sarah

by Heather Furey

06 June 2018

Well, here we are again – in the middle of the gray raw North Pacific in June; must be OSNAP time!

Amy Bower and I are the only OSNAP people on a ship full of Ocean Observatories Initiative (OOI) folks.  But almost everyone on this ship is from WHOI.  I will really miss sailing with Bill (Johns) and Stuart (Cunningham) and well, all the rest of the UMiami and SAMS crew, and sometimes the NIOZ crew, as I have done almost each year since 2014.   Your shipmates become like family, and it was nice to have the same science crew together as we bounced from ship to ship each year.  And I will miss seeing Rockall. This year, though, since the third and final seeding of RAFOS float deployments were completed in 2016, Amy and I are onto something else.

The RV Armstrong is here primarily for the turn-around of the OOI Global Irminger Sea Array off the eastern tip of Greenland (http://oceanobservatories.org/array/global-irminger-sea/).   Amy arranged with the National Science Foundation (NSF) for four additional days of shiptime and mooring crew time to deploy four moorings for OSNAP east of Greenland, and also to recover two of the sound source moorings used for tracking the RAFOS floats.  We took over this mooring array, instrumented with CTDs and current meters, from the UK as a swap: they took over some moorings in the Iceland Basin closer to their home country.  Although this is a turn-around year for these moorings, we are only doing the re-deployment.  Johannes Karstensen and Penny Holliday, onboard the RV MSMerian, will recover the moorings that were deployed by Penny onboard the RRS Discovery in 2016.  Johannes and Penny will be recovering at about the same time that we are deploying, and we will have to carefully coordinate our timing so that we do not literally get our equipment tangled up together.  Stay tuned on that one.

This cross-slope array will measure the properties and transport of the Deep Western Boundary Current which flows along the ocean bottom from north to south.  The DWBC is composed of two primary water sources, the Denmark Strait Overflow Water (DSOW) and the Iceland-Scotland Overflow Water (ISOW).  The DSOW is ‘newer’; its source is the dense (relatively cold and fresh) water that overflows the sill at the Denmark Strait, at the head of the Irminger Sea.  Above it resides the relatively saltier and warmer ISOW, which originally came from the head of the Iceland Sea, in a similar deep overflow, but much farther upstream.   Both are principal components of the subpolar overturning circulation.

One thing I like about being at sea is learning new things; things that have nothing to do with sitting in a chair at a desk on a computer.  This morning were the first release tests for the surface mooring (SUMO) at the OOI Irminger Sea Array.  Talking with Jim Dunn, a salty mooring technician from WHOI, I learned that it is common practice for the OOI team to test releases by lowering them to 1000 meters depth on the CTD frame, and to let them sit for 20 minutes to get cold before doing the test. The release needs to be acclimated and under pressure to make for a good test. Seems like every group has a slightly different depth and duration for wet tests of the releases.  Some groups do not do a wet test at all.  I’ll plan to stick to the OOI protocol for our own mooring releases.

As well, I got a good show-and-tell from Jim Dunn and Meaghan Donohue, another salty mooring technician from WHOI, about how wire is wound on a reel with respect to the winch.  On this ship, we have a Lebus winch, a double barreled winch where the barrels can be moved independently, at independent speeds, and also oriented differently from each other, or skewed, to control the spread of the loops on the reel – so they do not get tangled.  The tension is controlled by the number of loops wrapped around the two barrels.  Nominally there are six loops wrapped around the winch barrels as the mooring line and instrument are fed over the fantail into the ocean.  After one reel of wire is spooled out, the wire is tied off, and the next reel of wire is moved into place.  Instruments are put on the mooring either between the two wires, or clamped onto the wire itself.

A more traditional winch, a “normal” winch, is a TSE winch – with a single barrel.  The single barrel cannot have reels of wire fed to it, the wire tangles easily.  This means that all reels must be carefully fed onto the single barrel winch before deployment.  All segments, starting with the mooring bottom, are wrapped onto the barrel in order from bottom to top.  Then, at deployment time, the line is payed out from top to bottom.  This means that to deploy with a Lebus is generally twice as fast as deploying with a TSE. 

The two winches have one upstream difference: the wirerope or rope may be wound on the spools in opposite directions.  This winding preference is correctable at sea, but it takes a long, long time to rewind spools of wire on a 3000 meter mooring, with the wire split onto many spools.  And at sea, it is best to be prepared.  Months before leaving for sea, I notified WHOI’s Rigging Shop that these moorings would be deployed on this ship with a Lebus winch. 

Our OSNAP mooring deployments are days off.  This morning (Wednesday 06 June 2018) we went out to make sure the OSNAP mooring wire rope was wound on the spools correctly, and it was.  Thank you, WHOI Rigging Shop.  For the Lebus winch, the top of the wire is on the outside of the spool, and the opposite holds true for the TWE winch.    If there are no instruments clamped to a wire segment, this wrap direction is inconsequential.  But if the wire segment is ‘marked’, which means an instrument like a microcat will be attached with clamps to the wire, rather than being deployed in-line, the wirerope is taped at the correct depth where the instrument will be attached on the mooring.  For this reason, marked reels need to be wound properly with respect to the winch used.

Jim also told me that moorings are deployed anchor first in ice-covered water.  Which I did not know and had never thought about.  You can’t steam into anchor-over position dragging a mooring cable through the ice, like you do with a mooring deployment in open water.  So in ice-covered water, the desired anchor position is where the mooring deployment starts.  Which means the exact opposite holds true for the winch type and wire wrapping relationship if you have an ice-deployed mooring.

What amazes me is that the same attention to detail needs to be paid to nearly every system set or tasks performed on a research cruise.  I think it will be great sailing with this new group of folks. 

The Lebus winch in action, its two barrels slightly skewed. Meaghan and Jim are at the center of the action, along with ‘deck boss’ John Kemp.

An unmarked reel – terminations are only labeled with shot length and the spool does not include ‘MARKED’ on the labelling.

A marked spool. The cable termination is labeled ‘top’ and the spool is labelled ‘marked’.

by Nicolai Bronikowski

Most of the MSM-74 scientists in the CTD watch room. I am in the middle with the blue shirt, to the right are from nearest to farthest: Sunke Schmidtko, Marie Hundsdoerfer, Ciara Willis and Johannes Karstensen. On the left are: Arne Bendinger, Rene Witt, Ilmar Leimann, Dasha Atamanchuk and Claire Normandeau. Missing from the photo are: Thea Siuts and Alexandre Barboni (Photo Credit: Joachim Ribbe).

Some of you have maybe wondered what life on a research ship is like. Maybe because you are about to embark on a cruise of your own, or maybe you are just curious. For me this is my first oceanographic cruise and even though I have only been on board for a week, I feel the ship routine settling in. Time to write a blog entry about a life at Sea! Most of the scientific work on board MSM-74 is centered on mooring and CTD work and we are all assigned shifts in which we carry out shared scientific duties. My shift for example is from 8 Am to noon and from 8 PM to midnight. During this time, we watch the CTD as it is collecting ocean data in the control room and then take bottle samples of salt and oxygen once the CTD is back on deck. During mooring work we are mostly on deck helping the crew and the three GEOMAR technicians Christian Begler, Rene Witt and Wiebke Martens with getting instruments ready. Often other shifts will help out on mooring work as there is a lot to do and the work can be physically demanding.

Working hard on cleaning up the recovered moorings.(Photo credits: Nicolai Bronikowski)

Technician team from GEOMAR. From left to right: Rene Witt, Wiebke Martens and Christian Begler. (Photo credits: Nicolai Bronikowski)

Every day at 1 PM we have science meetings were progress and plans are discussed by the chief scientist of our cruise Johannes Karstensen from GEOMAR. This is the time ask questions and sometimes it is also a good place to share the results of your work. For example, today Penny Holliday who I interviewed in Blog #2, described her OSNAP work and some of the surprising results that came out of OSNAP with respect to the role of the Labrador Sea in the overturning circulation.

Science Meeting photo from Penny’s talk. (Photo credit: Joachim Ribbe)

Our kitchen team feeds us well with three hot meals a day. Breakfast is from 7:30 to 8:30, Lunch is 11:30 to 12:30 and dinner is from 5:30 to 6:30 PM. And don’t forget the cake at 3 PM! Typically meals are eaten by the first shift to relieve the other one so they can eat as well. Everyday the fantastic chefs of MSM-74 prepares vegetarian as well as meat options for everyone on board. If one is afraid of missing out on a meal the person can request their meal to be kept in the fridge to be eaten later. Sylvia, the stewardess also runs the ships store were twice a week one can purchase a few necessities such as fruit gummies, chocolate or toiletries. The typical after work beer is allowed on board of course so the shop also offers duty free beverages such as beer and liquor.

Eating “Mustard Eggs” “Eggs with mustard sauce and beetroot” for dinner. A traditional German dish! (Photo Credit: Joachim Ribbe).

After a hard day working on deck there are various ways to relax such as going to the ships own Sauna with a real Finnish made sauna room and beach chairs to relax afterwards. In ships storage area there are table tennis, darts as well as a foosball table and they often become the center of socializing after work shifts are over. In the ship’s own bar one can purchase drinks and relax in leather chairs to the sound of music or an interesting conversation. Game nights are also held there and it’s a good meeting place to talk more to the crew.

Typically, there are two scientists that share a room, except for the technicians and principal investigators that get their own cabin on board the ship. The way the shifts tend to work out one goes to bed as the other gets up for their shift. Which is a good system for those that need a bit of alone time or are light sleepers. And one can wake up each other Curtains help keeping light out and for the most part you don’t notice people entering or leaving. If one feels like they need to be out and relax, when the weather is good there is a nice little bench on the port side of the main deck and for those who like to sunbath in the chill air, there are beach chairs on the observation deck

I hope this summary of typical day on board and the different routines help paint a clear picture of life at sea on the Maria S. Merian. We are now close to Greenland on our month long cruise and I am excited for the next couple of days enjoying Greenland’s coastline.

By Nicolai Bronikowski

Blog Entry 2:

There are many fantastic people from all corners of the world on board of our cruise and in the next few entries I like to introduce some of these people I have the pleasure dealing with every day. One of our scientists, Penny Holliday is an ocean going oceanographer from NOC (National Oceanography Centre), who joined our cruise from Southampton, UK. Penny has worked in Ocean science for over two decades and leads the UK OSNAP program.

Penny told me what really got her interested in Oceanography was the possibility to work on so many projects and how connected everything about the ocean is. Penny herself calls her starting point in oceanography a coincidence. Penny was analysing a hydrographic time series when she noticed that her data set could not be explained without digging deeper into the wider Atlantic circulation. This was her starting point in studying the currents in the North Atlantic, which is the focus of the OSNAP program.

But why does this transport matter? It may not be obvious to think about the cold North Atlantic as an important driver of our pleasant weather in Europe. Penny told me that without the currents in the North Atlantic transporting water South-North which is called the Meridional Overturning Circulation, the weather in Europe would be much colder than it is now. Indeed, understanding the way this circulation changes and what drives it are in Penny’s view the key to adapting better to climate change.

I also asked Penny what she has most enjoyed about Oceanography and she admits it’s the travel and the opportunity to do lots of different things. To Penny one of the best things about oceanography are its interdisciplinary focus, with opportunity to work with lots of people. Penny is frequently on ships and her number one advice is to take the time to meet as many people as possible, make friends and be open to learn about topics that may not be directly related to your research focus.

Penny working on the mooring spool together with GEOMAR student Ilmar Leinmann (Photo credit: Penny Holliday)

On our cruise the last few days were filled with extracting and deploying moorings (K7-K10) and taking CTDs along the 53 North Array. The array stretches from the Newfoundland-Labrador shelf between depths of few hundreds to over 3000 meters deep. Most of the instruments we recover have been sampling for over two years and our task is to extract the data and ready them for the next mooring deployment with the OSNAP program. For us as young scientists we get to learn a lot of practical and technical skills changing batteries and calibrating the sensors and we feel the responsibility of doing a good job. After all the continued success of the program depends on new and accurate data.

Map of the 53 North Array and the total cruise plan for MSM 74.

Recovering Mooring K7 (Photo Credit: Sunke Schmidtko)

by Nicolai Bronikowski, Memorial University

Blog Entry 1:

Summary:

And we are off! MSM 74 – the oceanographic cruise from St. John’s to Reykjavik is making its way to the Labrador Sea. In these 5 weeks a group of 21 scientists and 24 crew on board the German research vessel “Maria S Merian”, will brace the tough North Atlantic in the name of science. The mission: we will recover and re-deploy German, British and US moorings with measurement devices as well as take 80 CTD casts from the surface to the ocean floor to assist the scientists from the OSNAP program with their effort to estimate the Subpolar Overturning circulation and associated transport of heat and freshwater. In this blog we will detail some of the work being done, why it matters to oceanography and what life on board feels like. We hope you will enjoy reading this blog.

Day 1 – Day 3: Our journey begins in St. John’s – the capital of the easternmost province of Canada: Newfoundland and Labrador. St. John’s is a vibrant little city on the Atlantic coast inside a natural harbour of ragged rocks towering around the fjord. The night before putting out to sea snow fell and for a moment coated much of the city in a fine layer of fine white dust. It must have been an unusual sight to see snow in the end of May for most of our team arriving from places where summer already started. Our team consists of 21 scientists, 6 of which are bio-geochemists from Dalhousie University (Canada) and 15 physical oceanographers from GEOMAR (Germany), Memorial University (Canada), NOC (UK) and EPPS (France).

After re-fuelling or bunkering as they say in nautical language, the ship’s ready for the voyage. The pilot boards the ship and helps the captain navigate safely into the open ocean. We all say goodbye to mainland until the end of cruise and are greeted by 2-4 meter swells. We began the journey with safety drills and figuring our safety equipment like entering the free-falling lifeboat and lifejackets.

After this was done it was time for our CTD test station (Station 27), just outside St. John’s. CTD stands for: Conductivity, Temperature and Depth sensor and is used to measure very precisely the temperature of the water. From conductivity, temperature and pressure, the salinity and density can be worked out using standardized equations for sea water. These variables are the most important physical variables captured on all ocean research cruises. However, our CTD cast has many more instruments attached such as an ADCP to measure current speeds, an oxygen sensor to measure dissolved oxygen, a flourometer to measure plant life activity, an altimeter to detect the distance to the seabed, and a UVP (underwater vision profiler) that takes high resolution pictures of living beings under water like plants, marine life and other particles. The CTD is attached to the so called rosette, which includes water bottles that can be closed at different depths and collect samples of sea water. These are then analyzed by the bio-geochemists for gasses such as oxygen or carbon dioxide as well as nutrients.

Everyone was present to learn about the different steps in taking a CTD cast and the necessary water sample preparations that needed to be done. Unfortunately, at this point, some of our scientific crew started to battle the effects of sea sickness and the ship’s doctor was doing his best encouraging us and gave us patches to counteract the sickness feelings. Now we are on our way to our first real mooring and CTD station site and we should arrive there this evening. Looking forward to what the day will bring.